ASBESTOS AND NO2 IN ENVIRONMENTAL LUNG DISEASE

描述 人体肺部暴露在环境颗粒和气体中 会导致多种疾病，包括肺纤维化和 癌症。我们研究小组之前的工作表明，石棉， 活性氧物种(ROS)和活性氮物种(RNS)触发 肺靶细胞中特定的细胞信号通路，导致 激活转录因子，如AP-1和NF-KB。这些和其他 转录因子参与细胞决策，导致 与肺部疾病的发生有关的表型变化。要延长 我们对细胞对化学和物理混合反应的理解 药剂，我们建议研究温石棉和氮气的影响 单独或同时暴露在三个暴露终点的二氧化碳(NO2)： 细胞存活、细胞周期进程和细胞凋亡。首先，我们将 大鼠肺上皮(RLE)细胞和大鼠肺的反应特征 成纤维细胞(RLF)对石棉和/或N02的激活作用 转录因子AP-1、NF-KB和E2F及其下游靶点 基因。细胞周期蛋白依赖性蛋白激酶(CDKs)的激活及其代谢 蛋白抑制物(即CKI p15、p6、p8、p21和p27)，以及 视网膜母细胞瘤家族蛋白(pRb和pl3O)的磷酸化将是 被研究为细胞周期进程的调节器。细胞成像技术， 将使用流式细胞术和蛋白水解酶的激活来检测细胞凋亡 回应。优势负性调控分子的瞬时表达 将被用来剖析暴露反应的机制。用于生理学 相关性，来自使用细胞周期控制模型和 体外的细胞凋亡将通过小鼠的吸入研究来验证。 最后，为了测试特定蛋白质如P53，CKIS， 以及细胞周期激活和/或其他候选细胞周期调节因子 将在#年进行石棉和N02、吸入引起的细胞凋亡研究 转基因小鼠缺乏感兴趣的特定基因。角色剖析 细胞周期和存活调节因子在增殖和凋亡中的作用 对石棉和N02共同作用的反应可能会导致新的 人体肺部暴露于化学混合物的生物标记物。

DESCRIPTION Exposure of the human lung to environmental particulates and gases contributes to a variety of diseases, including pulmonary fibrosis and cancer. Previous work in our research group has shown that asbestos, reactive oxygen species (ROS), and reactive nitrogen species (RNS) trigger specific cell signaling pathways in target cells of the lung, leading to activation of transcription factors such as AP-1 and NF-KB. These and other transcription factors are involved in cellular decisions leading to phenotypic changes involved in the initiation of lung disease. To extend our understanding of cellular responses to mixtures of chemical and physical agents, we propose to study the effects of chrysotile asbestos and nitrogen dioxide (NO2), either alone or together, on three endpoints of exposure: cell survival, cell cycle progression, and apoptosis. First, we will characterize the responses of rat lung epithelial (RLE) cells and rat lung fibroblasts (RLF) to asbestos and/or N02, in regard to the activation of the transcription factors AP-1, NF-KB, and E2F and their downstream target genes. Activation of cyclin-dependent kinases (CDKs), metabolism of their protein inhibitors (i.e., CKIs p15, pl6, pl8, p2l, and p27),and phosphorylation of retinoblastoma family proteins (pRB and pl3O) will be studied as regulators of cell cycle progression. Cell imaging techniques, flow cytometry and activation of proteases will be used to measure apoptotic responses. Transient expression of dominantnegative regulatory molecules will be used to dissect mechanisms of exposure responses. For physiological relevance, results from experiments using models for cell cycle control and apoptosis in Vitro will be verified by inhalation studies using mice. Finally, to test the contributions of specific proteins such as p53, CKIS, and other candidate cell cycle regulators in cell cycle activation and/or apoptosis by asbestos and N02, inhalation studies will be performed in transgenic mice lacking specific genes of interest. Dissection of the role of cell cycle and survival regulators in proliferative and apoptotic responses to the combined effects of asbestos and N02 may lead to new biomarkers for exposure of the human lung to chemical mixtures.